1. Field of the Invention
The invention relates generally to the art of contact body elements for gas and liquid contact apparatus, and more particularly, to an improvement to the stacking of contact bodies consisting of stacks of formed sheets. The improvement includes having adjacent sheets in the contact body offset from one another and supported on a contact body therebelow. This arrangement produces a larger space at the interface between stacked contact bodies so that the possibility of the passageways at such interface being blocked is reduced.
2. Description of the Art
It is known in the art to provide liquid-gas contact bodies which consist of formed layers of sheet material. For example, the sheets may be corrugated or folded, with folds in adjacent layers crossing one another. In large installations, these contact bodies are stacked one upon the other, usually with the sheets of one body positioned transversely to the sheets of the adjacent body. Such previously proposed contact bodies were formed of sheets having generally the same dimensions with their upper and lower edges all lying in the same plane. It has been found that such an arrangement causes restrictions at the interface between adjacent bodies. This results in stagnation of the liquid at the interface and deposition of solids suspended in the liquid at the interface which tend to block liquid and gas flow. This causes further stagnation of the liquid and clogging.
In has previously been proposed to prevent clogging at the bottom face of a single gas contact body at which air enters by providing adjacent sheets in pairs and cut obliquely at their edges so as together to form an inverted V viewed in the surface extension of the layers. A formed layer or sheet having a transversely cut straight lower edge is located between each such pair and extends downwards for a distance below the layers having the obliquely cut edges. This arrangement, shown in U.S. Pat. No. 3,738,626, has proved complicated to manufacture as well as expensive, because layers are cut both obliquely and transversely depending on their position.
Other attempts in reducing such an overbridging by water include increasing the height of the folds or corrugation of the layers, but then the capacity of the contact body within a certain volume is deteriorated to the same degree.